A well-defined focal plane resulting in blurring of background and/or foreground objects in photographs is one of the benefits of high quality, large aperture lenses. However, large apertures come with significant downsides. Such lenses are more expensive and difficult to manufacture; are heavier and larger than comparable smaller aperture lenses, and can dramatically magnify the impact of even minor errors in focus. For example, using an expensive 85 mm F/1.2 lens, open to its full aperture, a photographer may find the depth of field so narrow that if the focus is on the tip of the subject's nose, the eyes may be out of focus. Similarly, wildlife and sports photography are areas where a narrow depth of field delivers striking images of the player or animal isolated from its surroundings, but even a small amount of motion by the subject after focus has been set can result in the desired area moving out of the area of sharp focus.
Modern digital cameras are capable of delivering low-noise images at relatively high ISO, or light sensitivity, settings. Compared to film, or earlier digital sensors, modern sensors are many times more light-sensitive—and light sensitivity in sensors is increasing significantly each year. Combined with modern post-processing software and techniques, one of the biggest benefits of large aperture lenses (note that “large aperture” literally refers to the size of the aperture; apertures are actually numbered in reverse, so that the largest apertures have the lowest numbers, for example 1.2 is much larger than 8.0) is the ability to deliver a lot of light to the imaging surface, allowing adequate light to be delivered even in low light conditions. With each advance in sensor light sensitivity and noise reduction, the utility and value of this quality of large aperture lenses is reduced. Indeed, an F/4.0 lens mounted on a modern digital DSLR can now deliver quality photographs in light conditions that may have required an F/2.8 lens just a few years ago.
As lens aperture is reduced (i.e. as the F/number increases), the depth of field increases. A “pinhole” aperture delivers a functionally infinite depth of field. While the photons can literally interfere with each when the aperture becomes too small, cameras/lens combinations typically deliver high quality photographs with enormous depth of field at small lens apertures, such as f/11 or f/22. Such photographs, however, can appear unnatural and flat, as objects both near and far are rendered with comparably sharp focus. It would be desirable, therefore, to overcome these and other limitations of the prior art with a new camera system and method.